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Rotary AC/5

(Redirected from RAC/5)
Rotary AC/5
Production information
Type Ballistic (Direct, Rapid Fire)
Tech Base Inner Sphere (IS)
Clan Experimental[1]
Year Availability 3062 (FS)[2]
Technical specifications
Heat 1/shot[3][4]
Damage 5/shot[3][4]
Minimum Range --
Short Range Inner Sphere = 1-5[3]

Clan = 1-7[4]

Medium Range Inner Sphere = 6-10[3]

Clan = 8-14[4]

Long Range Inner Sphere = 11-15[3]

Clan = 15-21[4]

Aerospace Range Inner Sphere = Medium[3]

Clan = Long[4]

Tons 10[3]
Critical Slots Clan: 8[5]

Inner Sphere: 6[3]

Ammo Per Ton 20[3]
Cost (unloaded) 275,000[5]
Ammo Cost (per ton) 12,000[5]
BV (2.0) 247[6]
31 (Ammo)[6]


Developed in 3062 by the Federated Commonwealth, the rotary autocannon/5 (also rotary AC/5 or RAC/5) is based only loosely on the Autocannon/5. While it has the same bore, it is capable of firing up to six times as many rounds as its standard cousin, allowing it to deal up to three times the damage of even an Ultra AC/5. The weapon may be used to fire up to six times in a turn, with each additional shot giving the potential for increased damage. At the same time, each extra shot increases the amount of heat the autocannon builds and increases the chance for a jam. Like the Ultra autocannon, rotary autocannons are unable to make use of special munitions.[2]

Though initially prototyped in the mid-3050s it wasn't until the Light Autocannon entered production that the rotary autocannon became viable. The lighter weight barrels of the LAC were mated to stronger breeches derived from Ultra Autocannon to create the RAC.[7]

Clan Diamond Shark's engineers created their own Clan-tech version of the RAC/5, starting development in 3069, producing prototypes in 3073,[1] and finally starting line production in 3104 with the Clan-RAC/5 becoming widely available by 3145.[8]


The rotary AC/5 was manufactured on the following planets:

Mydron Tornado[edit]

The Tornado is a 150 mm cannon.[9]

Manufactured on Manufactured by Typically used in References
Gulkana Yeffters Weapons Factory DI Schmitt
MuckRaker MOD

Mydron Model RC[edit]

Mounted on the Legionnaire BattleMech, this autocannon fires depleted uranium tipped 50mm shells.[11]

Manufactured on Manufactured by Typically used in References
Cahokia Achernar BattleMechs Legionnaire [12]


  • This article refers to a common object and addresses the object as a common noun. The preferred terms are "rotary autocannon/5" or "rotary AC/5" (except on section titles & table headings, where "Rotary Autocannon/5" or "Rotary AC/5" are favored).


  1. 1.0 1.1 Tactical Operations, p. 286, "Clan Rotary Autocannon (RAC)"
  2. 2.0 2.1 TechManual, pp. 207-208, "Rotary Autocannon"
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 TechManual, p. 341, "Inner Sphere Heavy Weapons And Equipment Table"
  4. 4.0 4.1 4.2 4.3 4.4 4.5 Tactical Operations, p. 404, "Heavy Weapons And Equipment Combat Data"
  5. 5.0 5.1 5.2 Tactical Operations, p. 405, "Heavy Weapons And Equipment Construction Data"
  6. 6.0 6.1 TechManual, p. 317, "Inner Sphere Weapons and Equipment BV Table"
  7. Field Manual: Federated Suns, p. 158
  8. Interstellar Operations, p. 38 "Universal Technology Advancement Table"
  9. 9.0 9.1 A Call to Arms, Ch. 26
  10. Technical Readout: Irregulars, p. 50, "MuckRaker MiningMech MOD"
  11. A Call to Arms, Prologue
  12. Objectives: Federated Suns, p. 13,